If I drop my whole exhaust & replace it, headers to mufflers, & drop the cats, what type of effect will it have on my fuel economy?

 

don't know about v8 but i had a 2011 v6, change entire exhaust with
bbk longtube headers, x-pipe and mufflers and no difference in mpg.
Did increase hp and tq.

 

Nice! Thanks

 

Probably not gonna notice an increase in MPG. May be a decrease if you can't keep your foot out of it.

 

It will be a lot louder but not much difference in mpg.

 

No increase expected, I typically drive it timid because of these god forsaken gas prices. Thanks guys, once I get around to it (& the $ for it) I will be posting pics after each mod I stack on

 

I've had my full exhaust (Kooks long tubes, kooks o/r x-pipe, and slp axe-back) on for about 3 weeks and I average right at 20MPG highway driving at 75MPH. That's also running with a 93 Race tune from Bama. I've yet to put the street tune on it to see what kind of mileage I would get. If you put the headers on yourself be prepared for some chaos, it's a PITA. If you have any questions about it send me a messege and I'll tell you what all I went through putting them on. The instructions can be deceiving...

 

Why does everyone keep calling the Kooks long tubes? They are a mid length header. Even Kooks themselves calls them mid lengths.